Dry clutch transmissions tend to provide higher coefficients of friction than wet clutches, however, dry clutches may have more thermal management issues. Some powershift dry dual-clutch transmissions (or “DCTs”) comprise a manual clutch construction, e.g., as disclosed in U.S. Patent Publication No. 2010/0113216 titled “Temperature Control of Dual Input Clutch Transmission,” which is herein incorporated by reference in its entirety. The '216 publication teaches the use of a controlled fan to improve cooling in the transmission. The indirect air flow path from the fan to the heat source can slow down the cooling process.
Another way to manage dry-clutch transmission temperatures is to link an air tank to the transmission housing. Japanese Patent Publication No. JP3209029 titled “Cooling Device for Electromagnetic Coupling Device With Magnetic Particle” to Kazou et al. discloses an air compressor driven by the exhaust energy of an engine configured to produce compressed air stored in a reserve tank that is in fluid communication with the transmission housing. This design requires a reserve tank which can add weight to the vehicle and increase part costs.
Therefore, it is desirable to have a dry-clutch transmission with a streamlined cooling system that can directly pressurize the transmission clutch housing. Moreover, it would be beneficial to have other vehicle subsystems tap into the compressed air provided by the transmission cooling system to reduce parts, assembly time and vehicle weight.